The Cutty Sark afloat

Grimshaw’s masterstroke was to lift the clipper off its dry dock floor, creating an astounding and functional basement space

The distended double-ogee section of the Cutty Sark’s hull tapers to blunt ridges at its keel, prow and stern and is clad in golden Muntz metal, lending it an antique sheen. Launched in 1869, it is the last surviving tea clipper, and the lacy brass nosings on its weather deck are wearing thin. It is quintessentially Victorian, infused with romanticism, but forged in an ultimately pragmatic world: the archetypical tight ship, built for John ‘Jock’ Willis, who wanted it to bring home the first of the new season’s tea from China with minimal operational costs.

It bankrupted Scott & Linton, the shipbuilders whose designer, Hercules Linton, envisaged a hybrid of the bow lines of Willis’s earlier ships and the hulls of Firth of Forth fishing boats, using composite timber and iron technology to make it fast and strong. Later, carrying wool, it broke records, with a 73-day passage from Sydney to London and speeds up to 17.5 knots (20mph) under Captain Woodget, who braved treacherous seas, icebergs and storms, and it became the ‘last chance ship’ for England’s January wool sales.

But when clippers were eclipsed by steamships, Willis sold it to a Portuguese firm in 1895 and it was eventually bought by the Incorporated Thames Nautical Training College in Greenhithe, which couldn’t afford its upkeep, before sailing down the Thames to a dry berth in Greenwich, saved from the scrapyard by the Cutty Sark Society, and opening to the public in 1957. The subsequent phase of this after-life began last month, after a comprehensive six-year conservation project with Grimshaw as architect and Buro Happold as structural engineer.

This project was precipitated by a survey which urged action to rectify the deformation and deterioration of its structure. ‘It would have become dangerous, and therefore likely to be taken down,’ says Buro Happold partner Steve Brown. Having rested on its keel since 1954, with no water to provide resistance, the sides of its hull were sagging under their own weight and everything they carried was sinking, except the masts, whose loads were resisted by the keel resting on the dry berth’s mass concrete floor. As the hardwood planks of the hull, themselves in need of repair, were methodically removed, it became apparent that its wrought iron ribs were badly corroded, contributing to the hull’s sagging action. Some had completely dissolved.

‘The most important thing was the shape of hull,’ says Grimshaw director Chris Nash. The other criteria were to preserve as much of the original fabric as possible, to improve access, means of escape, facilities and the quality of the internal environment and displays and to ensure the continued use of the ship as a museum and venue for other events, which would generate revenue to fund future conservation work. Grimshaw also had to be mindful of the ship’s context and landscaping work to Cutty Sark Gardens, conceived as the gateway to the Maritime Greenwich World Heritage Site.

The objective was to conserve the ship for a further 50 years and this was achieved by removing the salt that had corroded the iron structure and coating it with specialist protective paint, installing steel replacement ribs, reinstating the keel and restoring the weather deck, Muntz metal protective hull cladding and the rigging – all 11 miles of it – to their original spec.

Grimshaw also relocated the main point of entry to the ship, rationalised circulation, removed offices and workshops to open up views within spaces which had become cluttered, added a new staircase, replaced a 1950s staircase with a platform lift and provided additional lift and stair access and other facilities in a new three-storey block adjacent to the ship. As far as possible, Grimshaw avoided touching the original fabric, locating vertical circulation in existing openings. About 90 per cent of the original hull construction was retained and everything done is reversible.

With a portfolio of adventurous new-build projects, Grimshaw seemed an unusual choice of architect for a conservation job. But this was no ordinary conservation. As well as being enormously complex and requiring a firm grasp of construction and engineering, it’s the Cutty Sark. The client correctly believed a resourceful, enterprising architect which, like Willis, Linton and Woodget, was not risk-averse, was needed. Grimshaw rose to the occasion by suggesting the project’s masterstroke.

More space was needed for display, catering and other facilities and events, but there was little available room on the site. So Grimshaw proposed raising the ship to create a 1,000 square metres of additional space below it on the dry dock’s floor, revealing its sixth elevation. ‘That was our idea, our biggest contribution,’ says Nash, who was inspired by the sight of a full-size replica of a blue whale suspended from a ceiling in London’s Natural History Museum.

The close proximity, presence and palpable weight of 963 tonnes of Muntz metal-clad clipper ship, propped up at its edges by 26 steel struts, make for a striking visitor experience, like viewing a biblical resurrection painting, or Damien Hirst’s shark. ‘I wanted it to be low enough so you could touch it, but no lower than that,’ says Nash. ‘Standing underneath it is quite unnerving,’ bleats a visitor. ‘Good!’ retorts Nash.

‘Initially, the project team thought lifting the ship was a bit of a barmy idea,’ says Nash. But it offered another convincing benefit. Conservation work to the existing iron structure and replacement ribs alone would not stop the hull sagging but, by raising the ship, it would be possible to remove the vertical compression forces acting on its hull and introduce 13 steel ‘coat hanger’ cradles to support the keel and masts, resting on the steel struts which act in conjunction with adjustable tension bars fixed to the walls of the dry berth. ‘The triangles take all the weight and none is taken by the ship,’ says museum and exhibition consultant Eric Kentley. The hull is also girdled by steel strake plates at ‘tween deck level, which hold the ribs.

‘The struts and ties, which stop the ship rocking under forces from the wind and visitor movements and help distribute the load, are arranged in various sizes and lengths, like a fan,’ says Nash. ‘The ship is very simply held, allowing us to monitor its position in space.’ The introduction of this pre-stressed structure might seem intrusive, as if aggressively degutting the vessel and stringing it out on an elaborate crinoline structure, but decisive action was called for and it has been carefully integrated. Proposals to re-float the ship on water would have required highly intrusive work.

After a fire in 2007, which delayed the project by 14 months, but caused only limited damage to the ship’s original fabric, Grimshaw proposed a canopy of triangular double-glazed units enclosing the space below the boat, which was to be air conditioned and supplied with under-floor heating. Depending on your viewpoint, this reads internally as a forest of fabricated steel sections or as a miniature version of Foster + Partners’ Great Court at the British Museum.

Externally, its reflective glass billows and tosses around facets like an opaque, abstracted ocean. The canopy is also an opportunity to locate the entrance, from which an arched bridge leads to an opening in the hull, which reveals its build-up. The bridge responds to the geometry of the hull and is supported by columns, inclined to identify them as part of a family of new construction. ‘We tried to have no verticals, so there’s no sense that the structure is supported, except by the struts,’ says Grimshaw project architect Den Farnworth. Similarly, all new steelwork is painted grey to distinguish it from the existing structure, which is white.

Grimshaw has single-mindedly and audaciously pursued the objectives of preserving the Cutty Sark by strengthening its fabric and guaranteeing its optimum continued use, providing visitors with a completely new experience of the ship and transforming an after-life to a rebirth, through the spirit and boldness of their proposals which are, like the Cutty Sark itself, a remarkable hybrid of the romantic and the pragmatic. ‘I think this is a real money-spinner,’ says Nash.

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